Sometimes, especially on weekend nights when it's hot and everybody's thirsty, there's barely room to move inside The Fairfax Market on P Street NW in the District.

Here's a well-dressed woman with a bag of Ruffles potato chips and a big bottle of tonic water, a Metrobus supervisor with a cup of coffee and a pack of cupcakes, a man holding three cans of Alpo. Six-packs of beer disappear into brown bags, a gray-haired man plunks a bottle of wine on the counter, somebody else wants a ham-and-cheese sandwich from the small deli counter in back.

Through it all, Sam Haddad and his three brothers, the proprietors of the small grocery-carryout at 2153 P St. NW near Dupont Circle, smile, nod and efficiently move the crowds along. They love that worn spot in the linoleum right in front of the checkout counter.

"Good night, my friend, take care," Sam calls as a regular customer disappears out the door. "Have a good evening, sir," he says to another.

Sam Haddad, 31, a robust Syrian native with a black mustache, loves the commotion. This is America, this is success.

"No matter what," he says, "the customer is king. When I have a full house, I'm a singing man."

There are hundreds of neighborhood markets in the metropolitan area. The products are often similar; personality distinguishes them.

People automatically seem to like Haddad and his brothers; The Fairfax Market is a friendly, easygoing place. Nobody blinks at the bearded fella carrying a guitar wrapped in plastic trash bags and secured with hundreds of rubber bands. The man in the silvery tutu is treated as graciously as the man in the pin-striped suit.

"I'm a believer in one thing. The good word and the bad word come out of the same place," said Haddad, pointing at his lips. "The good word is going to bring you five or 10 more customers. The bad word's only going to hurt.

"We get over a thousand people a day, and we call at least half of them by name. All of them call us by name."

"They like us," said his brother, George, 27.

Bryan Miles, a graphic designer who lives on nearby Massachusetts Avenue, drops by The Fairfax Market nearly every day for cigarettes, a soft drink or something.

"I grew up in a small town," Miles said, "and the nice thing about living in a small town is that you know the people and they're friendly. These guys have a commitment to the neighborhood. They're like what's-his-name on 'The Andy Griffith Show,' you know, Floyd, the barber.

"If I go out for a run and get back and need a bottle of water, they spot me. One of their family -- they have a lot of cousins -- jump-started my car the other day. They're all laid back. That Sam never gets ruffled."

Miles is standing on the worn spot in front of the cash register. "I owe you for a pack of cigarettes the other day," he tells Sam.

Which brother was it? Sam asks. "Was it the ugly one with the glasses?"

"All of you are ugly," Miles replies with a laugh.

The Fairfax Market is Sam Haddad's "baby," he likes to say. When he bought it four years ago from the previous owners who went bankrupt, he had already owned and operated a convenience store near the Washington Convention Center, a sandwich shop in the District, a pizza shop in Northern Virginia. With pride, he says that he built up the other businesses, then sold them at a large profit.

Haddad came to the Washington area from Syria in 1974, the first member of his family to do so. He was a computer science student first at Northern Virginia Community College, then at George Mason University. He also waited tables at an expensive French restaurant and saved every penny. At 19, he opened his first business, the Accommodation Market at 11th and H streets NW.

"I'm an active person. I didn't want to sit behind a desk. I didn't really like computer science. My father wanted me to have an education."

He grew up in a middle-class home with his six brothers and sisters. His father, Badi, was in the military; his mother, Rosa, made the boys work when they were 9 years old.

"The old lady, the pusher, she is the one," Haddad said. "So we wouldn't be out on the street, she created something for us to do. 'Go over to the neighbor's store and help with the customers,' she'd say. Not because we needed the money, but it was the principle -- to learn something. I became a real hustler for business."

Once Haddad became established here, he sent for his family -- brothers Mike, now 33, and Louie, 24, and George. He married, bought a house in Springfield, became father to a son, now 9, and a daughter, 7. His parents moved here in 1980, and his father, 62, often helps out in the store.

"Good boys, good sons," Badi Haddad said on a recent afternoon as he restocked the beer cooler. "Sam's a good man, smart. All my sons are smart, honest."

They are also, at this point, quite successful. That's good, their father said, but it doesn't mean that much by itself.

"The man makes the money," he said, "not the money makes the man."

Things are changing on P Street, renovation everywhere. The Fairfax Market, flanked by a shoe repair shop and a gay bar called "Mr. P's," has expansion plans, too.

The brothers intend to convert 700 square feet of unused space in the tan-and-brown building into the deli-carryout section, giving customers in the store area a little more elbow room. They're even talking about adding a few sidewalk tables, but they assure customers that the spirit of The Fairfax Market won't change.

The long hours required to run the store -- 60 to 70 hours a week for each brother, including an occasional 24-hour shift -- aren't likely to be reduced with the expansion. But Sam and his brothers, all of them U.S. citizens now, don't seem to mind.

"My wife understands the situation," Haddad said. "I'm not working for myself. I'm working for the family. My kids -- I'm trying to have something for them.

"This is our home. I left my other home 15 years ago and never went back. This is the place that has respected me."

He turned to a young woman in running clothes, a nightly customer looking for a certain fruit juice. "Yes, my friend," Haddad said with a smile, "how can I help you?"